Is this legal?
Private copying of copyrighted material is illegal in the UK, but the concern of this article is with rightful access to legally purchased Blu-rays. Unfortunately on Linux this requires digital circumvention – something that has been hotly debated for years and continually head-butts against Fair Use Rights.
In the United States, the Digital Millennium Copyright Act (DMCA) criminalises decrypting protected content (even if legally purchased), and US courts are still fighting over DMCA versus Fair Use, so you can take it the practice in the USA remains illegal.
UK law has been quite draconian in theory, but liberal in practice and has been under constant discussion for years, as the interests of copyright holders continue to run counter to practical realities. Personal copies are legal if you live in The Netherlands, Spain, or Australia, but do not distribute that material. The area is muddy as these laws are primarily for restricting the sharing of content, not keys. To further muddy the waters, circumvention tools may be legal for non-infringing purposes, but the production and distribution thereof will not be. Legal exceptions may exist for circumvention for the purposes of journalism [that’s us!–Ed], critique or comment, and non-commercial videos. So is this legal? We’re not lawyers and cannot answer that. Seek sound legal counsel.